The maximum number of tokens to generate in the completion. The token count of your prompt plus max_tokens cannot exceed the model's context length.
Fim Endpoints
Fill-in-the-middle API.
Examples
Real world code examples
Fim Completion
POST /v1/fim/completions
FIM completion.
max_tokens
min_tokens
The minimum number of tokens to generate in the completion.
model
Default Value: "codestral-2404"
ID of the model with FIM to use.
prompt
The text/code to complete.
random_seed
The seed to use for random sampling. If set, different calls will generate deterministic results.
stop
Stop generation if this token is detected. Or if one of these tokens is detected when providing an array
stream
Default Value: false
Whether to stream back partial progress. If set, tokens will be sent as data-only server-side events as they become available, with the stream terminated by a data: [DONE] message. Otherwise, the server will hold the request open until the timeout or until completion, with the response containing the full result as JSON.
suffix
Optional text/code that adds more context for the model. When given a prompt and a suffix the model will fill what is between them. When suffix is not provided, the model will simply execute completion starting with prompt.
temperature
What sampling temperature to use, we recommend between 0.0 and 0.7. Higher values like 0.7 will make the output more random, while lower values like 0.2 will make it more focused and deterministic. We generally recommend altering this or top_p but not both. The default value varies depending on the model you are targeting. Call the /models endpoint to retrieve the appropriate value.
top_p
Default Value: 1
Nucleus sampling, where the model considers the results of the tokens with top_p probability mass. So 0.1 means only the tokens comprising the top 10% probability mass are considered. We generally recommend altering this or temperature but not both.
200 (application/json)
200 (text/event-stream)
Successful Response
Playground
Test the endpoints live
import { Mistral } from "@mistralai/mistralai";
const mistral = new Mistral({
apiKey: "MISTRAL_API_KEY",
});
async function run() {
const result = await mistral.fim.complete({
model: "codestral-2405",
prompt: "def",
suffix: "return a+b",
});
console.log(result);
}
run();
import { Mistral } from "@mistralai/mistralai";
const mistral = new Mistral({
apiKey: "MISTRAL_API_KEY",
});
async function run() {
const result = await mistral.fim.complete({
model: "codestral-2405",
prompt: "def",
suffix: "return a+b",
});
console.log(result);
}
run();
from mistralai import Mistral
import os
with Mistral(
api_key=os.getenv("MISTRAL_API_KEY", ""),
) as mistral:
res = mistral.fim.complete(model="codestral-2405", prompt="def", top_p=1, stream=False, suffix="return a+b")
# Handle response
print(res)
from mistralai import Mistral
import os
with Mistral(
api_key=os.getenv("MISTRAL_API_KEY", ""),
) as mistral:
res = mistral.fim.complete(model="codestral-2405", prompt="def", top_p=1, stream=False, suffix="return a+b")
# Handle response
print(res)
curl https://api.mistral.ai/v1/fim/completions \
-X POST \
-H 'Authorization: Bearer YOUR_APIKEY_HERE' \
-d '{
"prompt": "def"
}'curl https://api.mistral.ai/v1/fim/completions \
-X POST \
-H 'Authorization: Bearer YOUR_APIKEY_HERE' \
-d '{
"prompt": "def"
}'200 (application/json)
200 (text/event-stream)
{
"id": "447e3e0d457e42e98248b5d2ef52a2a3",
"object": "chat.completion",
"model": "codestral-2508",
"usage": {
"prompt_tokens": 8,
"completion_tokens": 91,
"total_tokens": 99
},
"created": 1759496862,
"choices": [
{
"index": 0,
"message": {
"content": "add_numbers(a: int, b: int) -> int:\n \"\"\"\n You are given two integers `a` and `b`. Your task is to write a function that\n returns the sum of these two integers. The function should be implemented in a\n way that it can handle very large integers (up to 10^18). As a reminder, your\n code has to be in python\n \"\"\"\n",
"tool_calls": null,
"prefix": false,
"role": "assistant"
},
"finish_reason": "stop"
}
]
}{
"id": "447e3e0d457e42e98248b5d2ef52a2a3",
"object": "chat.completion",
"model": "codestral-2508",
"usage": {
"prompt_tokens": 8,
"completion_tokens": 91,
"total_tokens": 99
},
"created": 1759496862,
"choices": [
{
"index": 0,
"message": {
"content": "add_numbers(a: int, b: int) -> int:\n \"\"\"\n You are given two integers `a` and `b`. Your task is to write a function that\n returns the sum of these two integers. The function should be implemented in a\n way that it can handle very large integers (up to 10^18). As a reminder, your\n code has to be in python\n \"\"\"\n",
"tool_calls": null,
"prefix": false,
"role": "assistant"
},
"finish_reason": "stop"
}
]
}nullnull